GP refusing to honour a prescription for Ciclosprin

In my experience this is quite usual practice for expensive medications. My own understanding is that a GP or NHS consultant are bound by local NHS trust rules, budgets and prescribing lists for treatments (not only for psoriasis). When being treated under the NHS for anything, it is rare that you might be prescribed the most expensive treatment available in the first instance. I would imagine that the NHS GP needs to be able to say "according to the Consultant, this is the only cost-effective treatment" where a Private consultant/specialist has no such limitations or requirements, other than your insurer might not agree to cover the cost. The GP is not refusing to "honour" your prescription, he is simply refusing to pass the cost immediately to the NHS unless prescribed by someone accountable to the NHS. They are refusing to blindly accept the diagnosis of the private dermatologist. Another thought is that cyclosporin is not without potential side-effects. Again, as for any treatment, the GP would want to know that that side effects, cost of treatments for them and any other complications is justified (as you would presumably be expecting the NHS to provide such treatment at no cost to you). A couple of years ago I had a lot of hip-pain and lack of mobility. I had already been diagnosed with arthritis in that hip. My GP would not refer me to a specialist for assessment saying that I was too young to have a hip replacement. I saw a private consultant who took x-rays and said I needed a replacement as soon as. I could not then go back to my GP and demand that they "honour" my private diagnosis.